Re: [PATCH 3/5] Compiler Attributes: add more Clang documentation links

[Nathan Chancellor <nathan@kernel.org>]

On Sat, Aug 03, 2024 at 07:19:31PM +0200, Miguel Ojeda wrote:
> Some more documentation has been written in Clang for some of the
> attributes, thus link them.
> 
> In some cases, they only have a "No documentation." entry, but at least
> they are acknowledged (and documentation may be eventually written).

For what it's worth, I recall a message on Discourse about trying to
correct this, even if the solution is just to say "it's the same as
GCC":

https://discourse.llvm.org/t/documenting-our-attributes/70019

But I am not sure that really went anywhere :/

> In one case, the link has been updated instead, since the URI fragment
> changed.
> 
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Reviewed-by: Nathan Chancellor <nathan@kernel.org>

> ---
>  include/linux/compiler_attributes.h | 17 +++++++++++++----
>  1 file changed, 13 insertions(+), 4 deletions(-)
> 
> diff --git a/include/linux/compiler_attributes.h b/include/linux/compiler_attributes.h
> index 5d171a7f8cbd..2d1ad2a74a4e 100644
> --- a/include/linux/compiler_attributes.h
> +++ b/include/linux/compiler_attributes.h
> @@ -22,6 +22,7 @@
>  
>  /*
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-alias-function-attribute
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#alias
>   */
>  #define __alias(symbol)                 __attribute__((__alias__(#symbol)))
>  
> @@ -29,6 +30,7 @@
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-aligned-function-attribute
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Type-Attributes.html#index-aligned-type-attribute
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#index-aligned-variable-attribute
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#alignas-align-alignas-aligned
>   */
>  #define __aligned(x)                    __attribute__((__aligned__(x)))
>  #define __aligned_largest               __attribute__((__aligned__))
> @@ -50,7 +52,7 @@
>   * inlinable [-Wattributes]" is emitted).
>   *
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-always_005finline-function-attribute
> - * clang: mentioned
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#always-inline-force-inline
>   */
>  #define __always_inline                 inline __attribute__((__always_inline__))
>  
> @@ -79,6 +81,7 @@
>   * Note the long name.
>   *
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-const-function-attribute
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#const
>   */
>  #define __attribute_const__             __attribute__((__const__))
>  
> @@ -146,6 +149,7 @@
>   * Optional: only supported since clang >= 14.0
>   *
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-error-function-attribute
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#error-warning
>   */
>  #if __has_attribute(__error__)
>  # define __compiletime_error(msg)       __attribute__((__error__(msg)))
> @@ -186,6 +190,7 @@
>  /*
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Type-Attributes.html#index-mode-type-attribute
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#index-mode-variable-attribute
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#mode
>   */
>  #define __mode(x)                       __attribute__((__mode__(x)))
>  
> @@ -222,6 +227,7 @@
>   *   return [expression];
>   *
>   *  gcc: https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html#Statement-Attributes
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#fallthrough
>   */
>  #if __has_attribute(__fallthrough__)
>  # define fallthrough                    __attribute__((__fallthrough__))
> @@ -239,7 +245,7 @@
>   * Note the missing underscores.
>   *
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-noinline-function-attribute
> - * clang: mentioned
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#noinline
>   */
>  #define   noinline                      __attribute__((__noinline__))
>  
> @@ -269,8 +275,7 @@
>  
>  /*
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-noreturn-function-attribute
> - * clang: https://clang.llvm.org/docs/AttributeReference.html#noreturn
> - * clang: https://clang.llvm.org/docs/AttributeReference.html#id1
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#noreturn-noreturn
>   */
>  #define __noreturn                      __attribute__((__noreturn__))
>  
> @@ -323,6 +328,7 @@
>  
>  /*
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-pure-function-attribute
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#pure
>   */
>  #define __pure                          __attribute__((__pure__))
>  
> @@ -358,6 +364,7 @@
>  /*
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-used-function-attribute
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#index-used-variable-attribute
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#used
>   */
>  #define __used                          __attribute__((__used__))
>  
> @@ -384,6 +391,7 @@
>   * Optional: only supported since clang >= 14.0
>   *
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-warning-function-attribute
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#error-warning
>   */
>  #if __has_attribute(__warning__)
>  # define __compiletime_warning(msg)     __attribute__((__warning__(msg)))
> @@ -412,6 +420,7 @@
>  /*
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-weak-function-attribute
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#index-weak-variable-attribute
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#weak
>   */
>  #define __weak                          __attribute__((__weak__))
>  
> -- 
> 2.46.0
>